Gas Cap

[JBwell]

1980 r65.  The barrel of the gas cap just spins (the part with the threads on it).  Tried locking and unlocking but makes no difference.  Of course this results in the cap not tightening up enough to make good contact with the tank.  Fixable or replacement needed?  I have the new seal that goes at the top of the cap, and the one that fits where the barrel meets the cap, is there another?  Thanks everyone!

[Bob_Roller]

This happens on occasion, when you tighten the cap, never turn it until it ratchets or clicks, you'll have issues later on if you do .

One member here, Barry, has a procedure for this hopefully he'll post it later today .

In the interim, you can try pulling up on the cap handle and see if this will help getting the cap off .

[Barry]

My cap is still good so that's one procedure I don't have. AFAIK there was no official service bulletin or method from BMW to fix a rotating cap.

You can lock the two parts together by inserting a self tapping screw from below.  Snowbum describes this about half way down this page.
http://bmwmotorcycletech.info/fuel-caps-airheads-K.htm

There is another method described with a photo in this thread.
http://www.bmbikes.org.uk/Forum/viewtopic.php?t=9815

[JBwell]

Thanks for the info!  Luckily my gas cap was already off (don't know how it was removed but it was off when I bought the bike) but I was able to drill and install a pin, just like the article said, and I am good to go!  JON